Arc interrupting device



July 6, 1943. w. H. LANTZ, JR 2,323,476

ARC INTERRUPTING DEVICE Filed Aug. 7, 1942 2 Sheets-Sheet 1 INVEN TOR.

WILL/17M LL/9,1172, Jf

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ATTORN E Y July 6, 1943. w. LANTZ. JR 2,323,476

RC INTERRUPTING DEVICE Filed Aug. '7, 1942 2 Sheets-$hs9fi T.

INVENTOR.

W/LL/H/7 Lin/r2 1e BY QCAMM ATTORNE Y Patented July 6, 1943 ARC INTERRUPTING DEVICE William H. Lantz, Jr., East Orange, N. 1., assignor to Cole Electric Products Co. Inc.. Long Island City, N. Y., a corporation of New York Application August 7, 1942, SerlalNo. 454,045

11 Claims.

This invention relates to are interrupting devices for electrical switches.

One object of the invention is the provision of an arc interrupting device whichis effective to confine the arc to a restricted region in the neighborhood of one of the companion contact members and to quickly extinguish the are.

A further object of the invention is to provide an arc chute or chamber in which the companion switch contact members are engaged with and disengaged from each other and which is provided with a passage having an automatically operable closure means which permits the movement of the movable contact member and automatically closes said passage when the contact members are disengaged, and by so doing extrnguishes an are that might be drawn between the companion contact members.

Another object of the invention is to provide an arc interrupting device having arc-barrier members which are movable during the interruption of the switch in such manner as to present progressively different surface portions of said members to the arc during the disengagement of the contact members, whereby to obviate or reduce pitting or other deterioration of said arc-barrier members and to increase the rapidity of the arc extinguishing action.

The above and other objects, features and advantages of the invention will be more fully understood from the following description considered in connection with the accompanying illustrative drawings which show a preferred embodiment of the arc interrupting device of this invention.

In the drawings:

Fig. l'is a front view, in elevation, of a switch provided with are interrupting devices of the present invention, the movable contact members being in open or circuit interrupting position;

Fig. 2 is a side view of the switch;

Fig. 3 is a sectional view on the line 3-3 of Fig. 2;

Fig. 4 is a sectional view on the line 4-4.0f Fig. 1;

Fig. 5 is a sectional view on the line 55 of Fig. 4;

Fig. 6 is a sectional view on the line 6-5 of Fi 2; Fig. '7 is a view similar to Fig. 6, showing a modification.

In the drawings, the arc interrupting device of the present invention is illustrated as applied to each pole of a three-pole switch, but it will be understood that said are interrupting device can be utilized in a switch having any number 01 poles. Also, in the switch illustrated in the drawings, a simple handle is shown for directly actuating the movable contact members, it being understood, however, that any other switch actuating device can be used, and it being noted further that the arc interrupting device of the present invention is intended primarily for use in a switch operated by a quick make and break actuating mechanism.

Referring now to the drawings more in detail, the switch, which is here shown as provided with the arc interrupting device of the present invention, comprises an insulation panel or base l0 on which the switch terminals and the companion stationary and movable contact members are mounted. Each movable contact member I2 is of the knife-blade type and is mounted for pivotal movement in metal clips l4 carried by companion lugs l6 which are fastened to panel ill by screws l8. Each of said lugs it also carries a fuse or terminal clip 20. The stationary contact members are each constituted by a pair of spring clips 22 between which the companion knife blade or movable contact member I2 of the switch is received as in the usual switch'of the knife-blade type. Said stationary contact members are carried by companion lugs 24 fixed to base I0 by screws 26 and 28, the last mentioned screws projecting beyond the lugs 24 at the front of the panel to constitute terminal studs. As illustrated more clearly in Fig. 4, the free edges at which the companion movable contact members l2 engage and disengage the stationary contact members have inclined edge portions 30 at which said companion movable contact members first engage and disengage their respective stationary contact members. As here shown the movable contact members l2 areactuated by a bar 32 of insulation material provided with an operating handle 34. Bar 32 is fixed to contact members l2 by U-shaped metal holding members 36 fixed to the companion movable contact members l2 in any suitable way as by rivets 38 and secured to insulation bar 32 in any suitable way as by screws 40.

Each pole of the switch is provided with an arc interrupting device 42 of the present invention. Said arc interrupting device comprises a chamber formed by a pair of laterally spaced opposed walls 44, a rear end wall 46 and a lower front spacing portion 48 which also acts as astop for movable contact I2. A cut out 50 is provided at the lower rear portion of each chamber to make room for the attachment of a terminal connector to the terminal stud 26. Walls 64 and 46 and portion 66 are all formed of Bakelite or any other suitable insulation material, and are secured together in any suitable way as by bolts I2 which secure the rear ends of walls 44 to rear walls 66, and by a bolt 54 which secured the forward lower portions of said walls 44 to part 48.

The are interrupting device 42 is mounted on the stationary contact member of the switch being secured thereto in any suitable way as by means of a bolt 66 which passes through walls 44 and the companion clip members 22 of said stationary contact member. With this mounting of the arc interrupting device, the stationary contact member of the switch is positioned in the chamber between companion walls 44 and the companion movable contact member is engageable with and disengageable from said stationary contact member in said chamber. The movable contact member i2 is movable into and out of said chamber through the passage constituted by the end and front openings 66 and 80, respectively, of the arc chute or chamber. Said passage is provided with closure means which as here shown are constituted by a pair of cylindrical arc-barrier members 62 and 64 which are mounted in companion slots 66 formed in walls 64. Said cylindrical members 62 and 64 fit with a slight clearance in their companion slots 66 so that they can move toward and away from each other and can also rotate in their companion slots about their longitudinal axes. While members 62 and 64 are preferably cylindrical, they may be of other shapes, for example rectangular with bevelled edges.

It will be noted that members 82 and 64 are positioned between the companion contact members, in the open condition of the switch and are in the path of movable contact member I 2. Said members 62 and 64 are movable toward and away from each other transversely of the passage through which the movable contact member moves for engaging and disengaging the companion stationary switch-contact member. Said members 62 and 64 are normally held in abutting relation or contact with each other and are biased for movement toward each other by resilient means, here shown as flat metal springs 66. Each of said springs 88 is fixed at one end thereof to adjacent wall 44 and any suitable way as by a short bolt 10, each of said springs having near its free end an arcuate portion I2 which resiliently engages a peripheral portion of the companion members 62 and 64 in relative rotary contact therewith. Members 62 and 64 are preferably formed of Bakelite but may be formed of any other suitable material. As illustrated in Fig. 7 one of said members, here shown as member A; which corresponds to member 64, is formed of metal while the other member 62 is formed of insulation material.

As shown more clearily in Figs. 2 and 4, the cylindrical members 62 and 64 are positioned near the free end of the stationary contact member and are inclined in a direction extending from rear walls 46 toward part 68 of the chamber and preferably in the direction of inclination of edge portion 30 of the stationary contact member. By reason of this position and arrangement of members 62 and 64, any are which starts to form between the inclined edge portion 20 of the stationary contact member and the confronting edge portion of the companion movable contact member strikes adjacent surface portions of said members 62 and 64- F111- iii) ther, it will be observed that in the movement 01' the movable contact member l2 from its position in which it engages the companion stationary contact member to a position out of engagement therewith, said movable contact member must pass between members 62 and 64 at which time the latter are held in resilient engagement with the opposite sides of said movable contact member by springs 68 which, however, permit said members 62 and 64 to move away from each other against the action of said springs to make room therebetween for said movable contact member. Thus, the movable contact member I2 engages said members 62 and 64 during the opening of the switch and causes said members to rotate about their longitudinal axes, thus presenting progressively different surface portions thereof to the arc, which might be formed when the switch is opened. In this manner the arc is confined to the arc chute or chamber and by reason of the rotation of members 62 and 84 during the opening of the switch,

different and relatively cool surface portions of members 62 and 64 are presented to the arc with the result that the latter is rapidly extinguished while at the same time pitting or other deteriorating action of the are on said members 62 and 64 is substantially eliminated or greatly reduced. Further members 62 and 64 may be coated with a lubricant to provide continual lubrication of members i 2 and 22. While a single pair of members 62 and 66 are shown for a pair of companion contact members, there may be a series of pairs of closure members 62 and 66 for a pair of companion contact members.

Thus, it is seen that the arc interrupting device described above is well adapted to accomplish the objects of the invention. It will be understood, however, that while I have shown and described the preferred embodiment of my arc interrupting device, the latter may be embodied otherwise than as herein disclosed and that in the illustrated embodiment, certain changes in details of construction and in arrangement of parts might be made without departing from the underlying idea of this invention. Also as hereinbefore indicated, the arc interrupting device of the present invention can be associated with a single pole switch as well as with a switch with any other number of poles and it will be understood further that this invention can be applied to switches of types which differ from that of the illustrated switch. Therefore, I do not wish to be limited to the invention as herein speciilcally illustrated or described except to the extent which may be required by the scope of the appended claims.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. An arc interrupting device for an electric switch having companion relatively movable contact members, said device comprising a pair of laterally spaced walls between which one of said contact members is positioned and between which the other switch contact member is movable for engagement with and disengagement from the companion contact member, arc-barrier members mounted in said walls, respectively, for movement therein transversely of the space therebetween in the path of said other switch contact, from a first position in which said arcbarrier members are in engagement with each other to a second position in which said arc-barrier members are in laterally spaced relation allowing movement of said other contact member into and out of engagement with said companion contact member, and resilient means for releasably holding said arc-barrier members in said' first position.

2. An arc interrupting device for an electric switch having companion relatively movable contact members, said device comprising a pair of laterally spaced walls between which one of said contact members is positioned and between which the other switch contact member is movable for engagement with and disengagement from the companion contact member, each of said walls having an opening therein, a pair of arc-barrier members mounted in said wall openings, respectively, for movement toward and away from each other and positioned in the path of said other contact members for engagement by the latter in its movements for engaging and disengaging the companion contact member whereby said arc-barrier members are movable toward and away from each other under the control of said other contact member, and means for biasing said closure members for movement toward each other.

3. An arc interrupting device for an electric switch having companion relatively movable contact members, said device comprising a pair of laterally spaced walls between which one of said contact members is positioned and between which the other switch contact member is movable for engagement with and disengagement from the companion contact member, a pair of arc-barrier members movably mounted in said walls, respectively, normally in engagement with each other and mounted for movement toward and away from each other and positioned in the path of said other contact member for engagement by the latter in its movements for engaging and disengaging the companion contact member whereby said arc-barrier members are movable toward and away from each other under the control of said other contact member, said arc-barrier members being cylindrical and mounted for rotation about their respective longitudinal axes, said arc-barrier members being positioned in relation to said contact members so that said engagement of said other contact member with said arc-barrier members is between said arc-barrier members at adjacent peripheral surface portions thereof and so that said arc-barrier members are rotated during the disengagement of said companion contact members.

4. In a switch having a stationary contact member and a companion movable contact member, said stationary contact member having an inclined edge portion at which, said movable contact member first disengages said stationary contact 'member during the opening of the switch, an arc interrupting device comprising a chamber in which the disengagement of said companion contact members occurs, and a pair of arc-confining members positioned in said chamber outwardly of said inclined edge and extending longitudinally of and in parallel relation to said edge, said are confining members being mounted for movement toward and away from each other transversely of the path of said movable contact 'member to permit the passage of the latter therebetween in disengaging said stationary contact member.

5. In a switch having a stationary contact member and a companion movable contact member, said stationary contact member having an inclined edge portion at'which said movable contact member first disengages said stationary contact member. an arc interrupting device comprising a chamber in which the disengagement of said companion contact members occurs, and a pair of arc-confining members positioned in said chamber outwardly of said inclined edge. said arc confining members being cylindrical and mounted for rotary movement about their respective longitudinal axes parallel to said inclined edge and for movement toward and away from each other transversely of the path of said movable contact member to permit the passage of the latter therebetween in disengaging said stationary contact member, said arc-confining members being normally in abutting relation along a line parallel to said axes, and means for holding said arc-confining members in said abutting relation, said movable contact member engaging said cylindrical members therebetween and causing rotation thereof during the disengagement of said movable contact member from said stationary contact member.

6. An arc interrupting device for an electric switch having companion relatively movable contact members, said device comprising a pair of laterally spaced walls between which one of said contact members is positioned and between which the other switch contact member is movable for engagement with and disengagement from the companion contact member, said walls having openings therein, a pair of arc-barrier members mounted in said openings, respectively, for movement toward and away from each other and positioned in the path of said other contact member for engagement by the latter in its movements for engaging and disengaging the companion contact member whereby said arc-barrier members are movable toward and away from each other under the control oi! said other contact member, said arc-barrier members being cylindrical and mounted for rotation about their respective longitudinal axes in said openings, said arc-barrier members being positioned in relation to said contact members so that said engagement of said other contact member with said closure members is between said closure members at adjacent peripheral surface portions thereof and so that said arc-barrier members are rotated during the disengagement of said companion contact members, and means for holding said arc-barrier members resiliently in abutting relation along a line parallel to said axes.

7. In a switch having a stationary contact member and a companion movable contact member, said stationary contact member having an inclined edge portion at which said movable contact member first disengages said stationary contact member, an arc interrupting device comprising a pair of relatively movable arc-barrier members positioned between said stationary and movable contact members in the open condition of the switch and arranged so that it is necessary for said movable contact members to pass between said arc-barrier members in engagement therewith in order to disengage said stationary contact member, said members being cylindrical and mounted for rotation about their respective longitudinal axes, whereby said arc-barrier members are rotated by the engagement of said movable contact members in the movement thereof for disengaging said stationary contact member, and resilient means for normally holding said arc-barriers in contact with each other along a line parallel to their axes.

33. In a switch having relatively movable companion contact members engageable with and disengageable from each other for closing and opening the switch, a pair of relatively movable arc-barrier members positioned between said companion contact members in the open condition of the switch and arranged so that it is necessary for one of said contact members to pass therebetween for disengaging the other of said contact members, said arc-barrier members being cylindrical and mounted for rotation about their respective longitudinal axes, and means holding said arc-barrier members releasably in abutting relation along a line parallel to said axes thereof whereby it is necessary for said con tact member which passes therebetween to engage said arc-barrier members and thereby rotate the same while disengaging said other contact member.

9. In a switch having relatively movable companion contact members engageable with and disengageable from each other for closing and opening the switch, a pair of relatively movable arc-barrier members positionedbetween said companion contact members in the open condition of the switch and arranged so that itis necessary for one of said contact members to pass therebetween for disengaging the other of said contact members, said arc-barrier members being cylindrical and mounted for rotation about their respective longitudinal axes and mounted for movement toward and away from each other laterally of said axes, and means holding said arc-barrier members releasably in abutting relation along a line parallel to said axes thereof whereby it is necessary for said contact member which passes therebetween to engage said arc-barrier members and thereby rotate the same while disengaging said other contact member, said arebarrier members being located sufliciently close to said other contact member to be engaged by the companion contact member when the latter is in arc-drawing relation to said other contact member.

10. In a switch having a stationary contact member and a companion movable contact member, said stationary contact member having an inclined edge portion at which said movable contact member first disengages said stationary contact member, an arc interrupting device comprising a pair of relatively movable arc-barrier members positioned between said stationary and movable contact members in the open condition of the switch and arranged so that it is necessary for said movable contact members to pass between said arc-barrier members in engagement therewith in order to disengage said stationary contact member, said members being cylindrical and mounted for rotation about their respective longitudinal axes and mounted for movement toward and away from each other laterally 0! said axes, whereby said arc-barrier members are rotated by the engagement of said movable contact members in the movement thereof for disengaging said stationary contact member, and means for holding said arc-barrier members in abutting relation along a line parallel to said axes thereof whereby it is necessary for said movable contact members to engage said arcbarricr members and thereby rotate the same while disengaging said stationary contact member, said arc-barrier members being sufficiently close to said stationary contact member to be engaged by the movable contact member as soon as it is in arc-drawing relation to said stationary contact member.

11. In a switch having relatively movable companion contact members engageable with and disengageable from each other for closing and opening the switch, a pair of relatively movable cylindrical arc-barrier members positioned between said companion contact members in the open condition of the switch and arranged so that it is necessary for one of said contact members to pass therebetween for disengaging the other'of said contact members, said arc-barrier members being rotatable about their longitudinal axes, and means for releasably holding said arebarrier members in abutting relation, at least one of said arc-barrier members carrying a lubricant which is applied to said one of the contact members and by the latter to its companion contact member.

WILLIAM H. LANTZ, JR. 

